/*
* Copyright (c) 2006-2009 Erin Catto http://www.box2d.org
*
* This software is provided 'as-is', without any express or implied
* warranty.  In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/

#include "Test.h"
#include "GLES-Render.h"

#include <stdio.h>

void DestructionListener::SayGoodbye(b2Joint* joint)
{
    if (test->m_mouseJoint == joint)
    {
        test->m_mouseJoint = NULL;
    }
    else
    {
        test->JointDestroyed(joint);
    }
}

Test::Test()
{
    b2Vec2 gravity;
    gravity.Set(0.0f, -10.0f);
    m_world = new b2World(gravity);
    m_bomb = NULL;
    m_textLine = 30;
    m_mouseJoint = NULL;
    m_pointCount = 0;

    m_destructionListener.test = this;
    m_world->SetDestructionListener(&m_destructionListener);
    m_world->SetContactListener(this);
    m_world->SetDebugDraw(&m_debugDraw);
    
    m_bombSpawning = false;

    m_stepCount = 0;

    b2BodyDef bodyDef;
    m_groundBody = m_world->CreateBody(&bodyDef);

    memset(&m_maxProfile, 0, sizeof(b2Profile));
    memset(&m_totalProfile, 0, sizeof(b2Profile));
}

Test::~Test()
{
    // By deleting the world, we delete the bomb, mouse joint, etc.
    delete m_world;
    m_world = NULL;
}

void Test::PreSolve(b2Contact* contact, const b2Manifold* oldManifold)
{
    const b2Manifold* manifold = contact->GetManifold();

    if (manifold->pointCount == 0)
    {
        return;
    }

    b2Fixture* fixtureA = contact->GetFixtureA();
    b2Fixture* fixtureB = contact->GetFixtureB();

    b2PointState state1[b2_maxManifoldPoints], state2[b2_maxManifoldPoints];
    b2GetPointStates(state1, state2, oldManifold, manifold);

    b2WorldManifold worldManifold;
    contact->GetWorldManifold(&worldManifold);

    for (int32 i = 0; i < manifold->pointCount && m_pointCount < k_maxContactPoints; ++i)
    {
        ContactPoint* cp = m_points + m_pointCount;
        cp->fixtureA = fixtureA;
        cp->fixtureB = fixtureB;
        cp->position = worldManifold.points[i];
        cp->normal = worldManifold.normal;
        cp->state = state2[i];
        ++m_pointCount;
    }
}

void Test::DrawTitle(int x, int y, const char *string)
{
    m_debugDraw.DrawString(x, y, string);
}

class QueryCallback : public b2QueryCallback
{
public:
    QueryCallback(const b2Vec2& point)
    {
        m_point = point;
        m_fixture = NULL;
    }

    bool ReportFixture(b2Fixture* fixture)
    {
        b2Body* body = fixture->GetBody();
        if (body->GetType() == b2_dynamicBody)
        {
            bool inside = fixture->TestPoint(m_point);
            if (inside)
            {
                m_fixture = fixture;

                // We are done, terminate the query.
                return false;
            }
        }

        // Continue the query.
        return true;
    }

    b2Vec2 m_point;
    b2Fixture* m_fixture;
};

bool Test::MouseDown(const b2Vec2& p)
{
    m_mouseWorld = p;
    
    if (m_mouseJoint != NULL)
    {
        return false;
    }

    // Make a small box.
    b2AABB aabb;
    b2Vec2 d;
    d.Set(0.001f, 0.001f);
    aabb.lowerBound = p - d;
    aabb.upperBound = p + d;

    // Query the world for overlapping shapes.
    QueryCallback callback(p);
    m_world->QueryAABB(&callback, aabb);

    if (callback.m_fixture)
    {
        b2Body* body = callback.m_fixture->GetBody();
        b2MouseJointDef md;
        md.bodyA = m_groundBody;
        md.bodyB = body;
        md.target = p;
        md.maxForce = 1000.0f * body->GetMass();
        m_mouseJoint = (b2MouseJoint*)m_world->CreateJoint(&md);
        body->SetAwake(true);
        return true;
    }
    return false;
}

void Test::SpawnBomb(const b2Vec2& worldPt)
{
    m_bombSpawnPoint = worldPt;
    m_bombSpawning = true;
}
    
void Test::CompleteBombSpawn(const b2Vec2& p)
{
    if (m_bombSpawning == false)
    {
        return;
    }

    const float multiplier = 30.0f;
    b2Vec2 vel = m_bombSpawnPoint - p;
    vel *= multiplier;
    LaunchBomb(m_bombSpawnPoint,vel);
    m_bombSpawning = false;
}

void Test::ShiftMouseDown(const b2Vec2& p)
{
    m_mouseWorld = p;
    
    if (m_mouseJoint != NULL)
    {
        return;
    }

    SpawnBomb(p);
}

void Test::MouseUp(const b2Vec2& p)
{
    if (m_mouseJoint)
    {
        m_world->DestroyJoint(m_mouseJoint);
        m_mouseJoint = NULL;
    }
    
    if (m_bombSpawning)
    {
        CompleteBombSpawn(p);
    }
}

void Test::MouseMove(const b2Vec2& p)
{
    m_mouseWorld = p;
    
    if (m_mouseJoint)
    {
        m_mouseJoint->SetTarget(p);
    }
}

void Test::LaunchBomb()
{
    b2Vec2 p(RandomFloat(-15.0f, 15.0f), 30.0f);
    b2Vec2 v = -5.0f * p;
    LaunchBomb(p, v);
}

void Test::LaunchBomb(const b2Vec2& position, const b2Vec2& velocity)
{
    if (m_bomb)
    {
        m_world->DestroyBody(m_bomb);
        m_bomb = NULL;
    }

    b2BodyDef bd;
    bd.type = b2_dynamicBody;
    bd.position = position;
    bd.bullet = true;
    m_bomb = m_world->CreateBody(&bd);
    m_bomb->SetLinearVelocity(velocity);
    
    b2CircleShape circle;
    circle.m_radius = 0.3f;

    b2FixtureDef fd;
    fd.shape = &circle;
    fd.density = 20.0f;
    fd.restitution = 0.0f;
    
    b2Vec2 minV = position - b2Vec2(0.3f,0.3f);
    b2Vec2 maxV = position + b2Vec2(0.3f,0.3f);
    
    b2AABB aabb;
    aabb.lowerBound = minV;
    aabb.upperBound = maxV;

    m_bomb->CreateFixture(&fd);
}

void Test::Step(Settings* settings)
{
    float32 timeStep = settings->hz > 0.0f ? 1.0f / settings->hz : float32(0.0f);

    if (settings->pause)
    {
        if (settings->singleStep)
        {
            settings->singleStep = 0;
        }
        else
        {
            timeStep = 0.0f;
        }

        m_debugDraw.DrawString(5, m_textLine, "****PAUSED****");
        m_textLine += 15;
    }

    uint32 flags = 0;
    flags += settings->drawShapes            * b2Draw::e_shapeBit;
    flags += settings->drawJoints            * b2Draw::e_jointBit;
    flags += settings->drawAABBs            * b2Draw::e_aabbBit;
    flags += settings->drawPairs            * b2Draw::e_pairBit;
    flags += settings->drawCOMs                * b2Draw::e_centerOfMassBit;
    m_debugDraw.SetFlags(flags);

    m_world->SetWarmStarting(settings->enableWarmStarting > 0);
    m_world->SetContinuousPhysics(settings->enableContinuous > 0);
    m_world->SetSubStepping(settings->enableSubStepping > 0);

    m_pointCount = 0;

    m_world->Step(timeStep, settings->velocityIterations, settings->positionIterations);

    m_world->DrawDebugData();

    if (timeStep > 0.0f)
    {
        ++m_stepCount;
    }

    if (settings->drawStats)
    {
        int32 bodyCount = m_world->GetBodyCount();
        int32 contactCount = m_world->GetContactCount();
        int32 jointCount = m_world->GetJointCount();
        m_debugDraw.DrawString(5, m_textLine, "bodies/contacts/joints = %d/%d/%d", bodyCount, contactCount, jointCount);
        m_textLine += 15;

        int32 proxyCount = m_world->GetProxyCount();
        int32 height = m_world->GetTreeHeight();
        int32 balance = m_world->GetTreeBalance();
        float32 quality = m_world->GetTreeQuality();
        m_debugDraw.DrawString(5, m_textLine, "proxies/height/balance/quality = %d/%d/%d/%g", proxyCount, height, balance, quality);
        m_textLine += 15;
    }

    // Track maximum profile times
    {
        const b2Profile& p = m_world->GetProfile();
        m_maxProfile.step = b2Max(m_maxProfile.step, p.step);
        m_maxProfile.collide = b2Max(m_maxProfile.collide, p.collide);
        m_maxProfile.solve = b2Max(m_maxProfile.solve, p.solve);
        m_maxProfile.solveInit = b2Max(m_maxProfile.solveInit, p.solveInit);
        m_maxProfile.solveVelocity = b2Max(m_maxProfile.solveVelocity, p.solveVelocity);
        m_maxProfile.solvePosition = b2Max(m_maxProfile.solvePosition, p.solvePosition);
        m_maxProfile.solveTOI = b2Max(m_maxProfile.solveTOI, p.solveTOI);
        m_maxProfile.broadphase = b2Max(m_maxProfile.broadphase, p.broadphase);

        m_totalProfile.step += p.step;
        m_totalProfile.collide += p.collide;
        m_totalProfile.solve += p.solve;
        m_totalProfile.solveInit += p.solveInit;
        m_totalProfile.solveVelocity += p.solveVelocity;
        m_totalProfile.solvePosition += p.solvePosition;
        m_totalProfile.solveTOI += p.solveTOI;
        m_totalProfile.broadphase += p.broadphase;
    }

    if (settings->drawProfile)
    {
        const b2Profile& p = m_world->GetProfile();

        b2Profile aveProfile;
        memset(&aveProfile, 0, sizeof(b2Profile));
        if (m_stepCount > 0)
        {
            float32 scale = 1.0f / m_stepCount;
            aveProfile.step = scale * m_totalProfile.step;
            aveProfile.collide = scale * m_totalProfile.collide;
            aveProfile.solve = scale * m_totalProfile.solve;
            aveProfile.solveInit = scale * m_totalProfile.solveInit;
            aveProfile.solveVelocity = scale * m_totalProfile.solveVelocity;
            aveProfile.solvePosition = scale * m_totalProfile.solvePosition;
            aveProfile.solveTOI = scale * m_totalProfile.solveTOI;
            aveProfile.broadphase = scale * m_totalProfile.broadphase;
        }

        m_debugDraw.DrawString(5, m_textLine, "step [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.step, aveProfile.step, m_maxProfile.step);
        m_textLine += 15;
        m_debugDraw.DrawString(5, m_textLine, "collide [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.collide, aveProfile.collide, m_maxProfile.collide);
        m_textLine += 15;
        m_debugDraw.DrawString(5, m_textLine, "solve [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.solve, aveProfile.solve, m_maxProfile.solve);
        m_textLine += 15;
        m_debugDraw.DrawString(5, m_textLine, "solve init [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.solveInit, aveProfile.solveInit, m_maxProfile.solveInit);
        m_textLine += 15;
        m_debugDraw.DrawString(5, m_textLine, "solve velocity [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.solveVelocity, aveProfile.solveVelocity, m_maxProfile.solveVelocity);
        m_textLine += 15;
        m_debugDraw.DrawString(5, m_textLine, "solve position [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.solvePosition, aveProfile.solvePosition, m_maxProfile.solvePosition);
        m_textLine += 15;
        m_debugDraw.DrawString(5, m_textLine, "solveTOI [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.solveTOI, aveProfile.solveTOI, m_maxProfile.solveTOI);
        m_textLine += 15;
        m_debugDraw.DrawString(5, m_textLine, "broad-phase [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.broadphase, aveProfile.broadphase, m_maxProfile.broadphase);
        m_textLine += 15;
    }

    if (m_mouseJoint)
    {
        b2Vec2 p1 = m_mouseJoint->GetAnchorB();
        b2Vec2 p2 = m_mouseJoint->GetTarget();

        b2Color c;
        c.Set(0.0f, 1.0f, 0.0f);
        m_debugDraw.DrawPoint(p1, 4.0f, c);
        m_debugDraw.DrawPoint(p2, 4.0f, c);

        c.Set(0.8f, 0.8f, 0.8f);
        m_debugDraw.DrawSegment(p1, p2, c);
    }
    
    if (m_bombSpawning)
    {
        b2Color c;
        c.Set(0.0f, 0.0f, 1.0f);
        m_debugDraw.DrawPoint(m_bombSpawnPoint, 4.0f, c);

        c.Set(0.8f, 0.8f, 0.8f);
        m_debugDraw.DrawSegment(m_mouseWorld, m_bombSpawnPoint, c);
    }

    if (settings->drawContactPoints)
    {
        //const float32 k_impulseScale = 0.1f;
        const float32 k_axisScale = 0.3f;

        for (int32 i = 0; i < m_pointCount; ++i)
        {
            ContactPoint* point = m_points + i;

            if (point->state == b2_addState)
            {
                // Add
                m_debugDraw.DrawPoint(point->position, 10.0f, b2Color(0.3f, 0.95f, 0.3f));
            }
            else if (point->state == b2_persistState)
            {
                // Persist
                m_debugDraw.DrawPoint(point->position, 5.0f, b2Color(0.3f, 0.3f, 0.95f));
            }

            if (settings->drawContactNormals == 1)
            {
                b2Vec2 p1 = point->position;
                b2Vec2 p2 = p1 + k_axisScale * point->normal;
                m_debugDraw.DrawSegment(p1, p2, b2Color(0.9f, 0.9f, 0.9f));
            }
            else if (settings->drawContactForces == 1)
            {
                //b2Vec2 p1 = point->position;
                //b2Vec2 p2 = p1 + k_forceScale * point->normalForce * point->normal;
                //DrawSegment(p1, p2, b2Color(0.9f, 0.9f, 0.3f));
            }

            if (settings->drawFrictionForces == 1)
            {
                //b2Vec2 tangent = b2Cross(point->normal, 1.0f);
                //b2Vec2 p1 = point->position;
                //b2Vec2 p2 = p1 + k_forceScale * point->tangentForce * tangent;
                //DrawSegment(p1, p2, b2Color(0.9f, 0.9f, 0.3f));
            }
        }
    }
}
